Kubuntu Crashes, Third Time

[Jim]

Kubuntu 7.10
Bootup and Ubuntu "Boot Menu" comes up and when Kubuntu starts , Error 
15: File not found.  .....Press any key to continue.  I press key and 
get same error message.

This is the third time that Kubuntu has crash like this on this Laptop 
and I have to reinstall each time.
I have XP, Fedora, and Kubuntu installed on Laptop, Fedora 8 or XP 
doesn't have any problems of booting from
Ubuntu Boot Menu, it's just Kubuntu that crashes.